Not Applicable
Not Applicable
The present invention generally relates an engine driven arc welder or welding apparatus and, more particularly, to such an apparatus which is portable and provides high power DC and AC outputs for selectively welding or operating power tools.
Conventional electrical systems for engines of motor vehicles such as trucks and automobiles typically include a DC battery, a dynamo adapted to deliver low voltage DC power, and a voltage regulator controlling the output voltage of the dynamo in response to the charge variation of the battery. Typically, the dynamo is an alternating current generator or alternator. Conventional alternators include a rotor which is driven by the engine via a pulley/belt system and a stator having three windings which are usually arranged in a wye configuration or a delta configuration to provide three phase AC output. The alternators typically have a rectifying circuit adapted to transform the AC output to DC which is then used to power the motor vehicle electrical system and charge the battery. Conventional alternators have only the DC taps exposed and not the AC taps.
Additionally, portable welding apparatus are known which include engine driven alternators to provide the necessary DC power. While such alternators may generate sufficient amps to operate some direct current welders, they provide limited amps such that all welder can not be operated and thus all material cannot be welded. Additionally, such alternators do provide the necessary AC power to operate auxiliary power tools such as, for example, lights. Accordingly, there is a need in the art for improved portable engine driven welding apparatus which generates necessary DC power to weld an increased variety of materials and/or the necessary AC power to operate auxiliary power tools.
The present invention provides a portable engine-driven welding which overcomes at least some of the above-noted problems of the related art. According to the present invention, a portable welding apparatus for use with a motor vehicle comprises, in combination, an internal combustion engine of the motor vehicle and an electrical current generating alternator operably connected to the engine to be driven thereby. The alternator is a three-phase AC alternator having a DC rectifier which converts AC current to DC current using resistors across phase to lag each phase at 120 degrees allowing phases to operate simultaneously. Preferably, the alternator includes DC taps for welding and AC taps for powering auxiliary equipment. Additionally, the alternator preferably generates at least 300 amps AC and 300 amps DC.
According to another aspect of the present invention, a portable welding apparatus for use with a motor vehicle includes an internal combustion engine of the motor vehicle and an electrical current generating alternator operably connected to the engine to be driven thereby. The alternator is a three-phase AC alternator having a first DC rectifier which converts AC current to a first DC current with phases to operating simultaneously and a second DC rectifier which converts AC current to a second DC current with phases to operating simultaneously.
According to yet anther aspect of the present invention, a portable welding apparatus for use with an engine of a motor vehicle includes an electrical current generating alternator to be operably connected to the engine and driven thereby. The alternator is a three-phase AC alternator having a first DC rectifier which converts AC current to a first DC current using resistors across phase to lag each phase at 120 degrees allowing phases to operate simultaneously and a second DC rectifier which converts AC current to a second DC current using resistors across phase to lag each phase at 120 degrees allowing phases to operate simultaneously. The alternator includes a three phase armature having three windings and the first and second DC rectifiers each include six diodes connected to the armature, the diodes are configured in three parallel legs with each leg having two of the diodes, and the three legs are connected to separate ones of the three windings between the diodes. The first and second DC rectifiers each have two of the resistors, a first one of the resistors connects a first one of the legs with a second one of the legs between the diodes, and a second one of the resistors connects the second one of the legs with a third one of the legs between the diodes. Preferably, the armature is wound in a wye configuration.
From the foregoing disclosure and the following more detailed description of various preferred embodiments it will be apparent to those skilled in the art that the present invention provides a significant advance in the technology and art of portable welders. Particularly significant in this regard is the potential the invention affords for providing a high quality, reliable, high power, easily assembled, low cost portable welder. Additional features and advantages of various preferred embodiments will be better understood in view of the detailed description provided below.